Then why I can't buy the super-resistant tires again?
Because you already have them bruh.
Why don't you just repair the vehicle?
You have both the option in a window to repair to buy the tired again. If it's popped you can repair the vehicle including tires and body kit.
Why do you have to buy it again? Just to repair it? When you have the repairing option available in the same video from where you have bought Bullet resistance tire.